Encoder / Decoder

Encode, decode and inspect common web formats locally in your browser.

Input

Output

Standards & references

URI percent-encoding: RFC 3986, especially §2.1–2.4 — RFC 3986.
Web URL parsing / form query strings: WHATWG URL Standard, including application/x-www-form-urlencoded and URLSearchParams — WHATWG URL Standard.
JavaScript encodeURI() / encodeURIComponent(): ECMA-262 — ECMAScript Language Specification.
Base64, Base64URL, Base32 and Base16: RFC 4648, §§4–8 — RFC 4648.
UTF-8: RFC 3629 / STD 63 — RFC 3629.
HTML character references: WHATWG HTML Standard — HTML character references.
JSON strings and escaping: RFC 8259, especially §7; JSON is UTF-8 for interoperable exchange — RFC 8259.
JavaScript Unicode escape sequences: ECMA-262 lexical grammar (\uXXXX and \u{...}) — ECMA-262 lexical grammar.
JWT: RFC 7519; compact signed JWTs use Base64URL through JWS. Security guidance is in RFC 8725 / BCP 225 — RFC 7519 and RFC 8725.
JWS / JWE: RFC 7515 and RFC 7516 define the compact signing and encryption structures used by JWT — RFC 7515, RFC 7516.
Internet timestamps: RFC 3339 defines a profile of ISO 8601 used for Internet date/time strings — RFC 3339.
Unix / POSIX epoch: POSIX defines the Epoch as 1970-01-01 00:00:00 UTC and “seconds since the Epoch”; ECMAScript Date uses millisecond time values with the same epoch — POSIX.1-2024 and ECMA-262 Date.